Effects of the medium on the filterability of human red blood cells.

Red blood cell filterability as an appropriate method for evaluating red blood cell deformability was studied with different suspending media of erythrocytes. Comparison of autologous plasma and buffer suspensions of healthy subjects' erythrocytes showed no significant difference in filterability. Albumin alone resulted in a dose-dependent increase, while fibrinogen caused a decrease in red cell filterability. In the presence of fibrinogen, albumin showed controversial effects. The results suggest that measurements of red blood cells in their original surroundings give more accurate information about the microcirculation because plasma components may have a crucial influence on erythrocyte deformability.